Apparatus and Method for Protecting In-Ground Wood

ABSTRACT

An apparatus and method for decreasing rot and insect damage to in-ground wood increases the effective life of the wood. The combination of a waterproof sleeve that covers the in-ground portion of the wood, and a collar surrounding the wood above the ground, defines a barrier system that prevents microbes and insects from gaining access to the wood and prevents leaching of chemical preservatives and the like from the wood into the soil.

TECHNICAL FIELD

The present invention relates to an apparatus and method for decreasing rot and insect damage to in-ground wood and thereby increasing the effective life of the wood, and more specifically relates to a barrier system for in-ground wood that prevents microbes and insects from gaining access to the wood and prevents leaching of chemical preservatives and the like from the wood into the soil.

BACKGROUND

Wooden poles of a variety of descriptions are sunk into the ground for use as supports. Examples include posts for fencing, supports for decking and other structures, and utility poles. Wooden poles are used as fence posts for many different styles of fences because they are both highly functional and often very attractive. Although there are many techniques for building fencing using wooden posts, in a typically situation the post is sunk into the ground, typically in a pre-drilled or pre-dug hole, which is then filled in with soil, gravel or concrete. Some type of railing is then attached to the poles to complete the fencing.

The effective life of in-ground wood such as a wooden fence post depends on a variety of factors, including for instance the species of wood that is used, the soil conditions including the amount of moisture in the soil and the composition of the soil—microbial-caused caused decomposition of wood fiber eventually results in rot and insect damage can further weaken the posts. While some species of wood such as some types of cedar are notoriously long-lasting as fencing posts, all in-ground wood will eventually decompose and the post will therefore fail and need to be replaced. In some areas where there is significant moisture in the ground, wooden fence posts can fail in a matter of years from the combination of bacterial and other microbial decomposition of the wood and insect damage.

Treated wooden fencing has significantly improved the longevity of in-ground wooden posts. Treating wooden posts involves applying preservatives of various types to the wood so that microbial and insect degradation of the wood fibers is slowed or stopped. Treatments can include simple application of liquid preservatives, and more complicated processes that involve applying preservatives to the wood under pressure so that the preservatives penetrate into the wood.

Regardless of the way in which the wood is treated, the preservatives that are used often contain dangerous and toxic chemicals that could be harmful to health, or at least raise questions about their proper use in the environment. When pressure treated wood is used for in-ground applications such as fence posts, some of the chemicals used as preservatives can leach into the soil and the United States Environmental Protection Agency recommends that wood treated with the commonly used preservative chromated copper arsenate (“CCA”) should not be used in proximity to edible plants.

For these and a variety of other reasons, more and more consumers are questioning use of products that add such toxins to the soil and are therefore seeking out alternatives to use of treated wood. There is a need therefore for improved alternatives for use of wood for in-ground posts.

The present invention provides an apparatus and method for overcoming the problems of rapid wood decay and possible leaching of toxic compounds into the soil from treated wood products. The invention facilitates improved longevity of in-ground wood and even in circumstances where treated wood is used, the present invention prevents leaching of toxic compounds from the in-ground portion of the wood into the soil.

The invention is defined by a waterproof sleeve that surrounds the post below ground level and extends to a level just above ground level, and a collar that surrounds the post where it emerges from the ground. The sleeve defines a barrier between the post and surrounding soil that prevents migration of water across the barrier, and prevents microbes in the soil from exposure to the wood and associated decomposition, and prevents insects from gaining access to the wood. The collar is designed to encircle the post at the ground level and to surround the upper portion of the sleeve. The collar prevents moisture and debris from entering the sleeve, yet allows for evaporation of moisture from the sleeve and from within the interior of the collar.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood and its numerous objects and advantages will be apparent by reference to the following detailed description of the invention when taken in conjunction with the following drawings.

FIG. 1 is an elevational and partial cross sectional view of an exemplary in-ground fence post illustrating the sleeve and collar according to the present invention.

FIG. 2 is a perspective view of an illustrated embodiment of the collar according to the present invention.

FIG. 3 is a perspective view of a section of the collar illustrated in FIG. 2.

FIG. 4 is an end elevation view of the collar shown in FIG. 3.

FIG. 5 is a cross sectional view taken along the line 5-5 of FIG. 3, and including a band that secures the collar to the post.

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS

A first illustrated embodiment of an apparatus 10 for protecting in-ground wood according to the present invention is illustrated in FIGS. 1 through 5. As noted previously, the apparatus 10 according to the present invention comprises a sleeve 12 and a collar 14, both of which surround a fence post, which is identified herein with reference number 16. Relative directional terms are used at times to describe parts of the invention and relative positions of the parts. As a naming convention, the ground plane is considered to be the surface of the ground (reference number 18) and, for purposes herein, is considered to be horizontal although of course in use the ground plane has slope and irregularities. Other relative directional terms correspond to this convention: “upper” refers to the direction above and away from the ground plane; “lower” is generally in the opposite direction, and so on.

The invention is described with reference to use of the invention with an in-ground fence post. It will nonetheless be appreciated that the invention is not limited to use with fence posts but instead may be used with any type and size of in-ground wood, such as deck supports, telephone and utility poles, and the like. The posts may have any cross sectional configuration, such as square, round, or irregular.

Sleeve 12 defines a waterproof casing that encloses the post 14 where the post is below the ground level 18—dimension C, FIG. 1. The sleeve 12 is preferably a plastic material such as polyethylene that is formed with a size and shape that corresponds to the shape of the post. The sleeve has a side wall portion 20 that extends vertically along the sides of post 16, a bottom portion 22 that lies below the bottom of the post, and an open top 24 through which the post 16 is inserted—the sleeve is essentially a bag that covers and contains that portion of the post that is below the level of the ground. The sleeve 12 may be formed as a cylinder or any other shape so long as the sleeve is large enough in interior diameter that the post 16 may be inserted into the sleeve. The sleeve fits relatively loosely around the post—as detailed below, when the post is sunk into a post hole in the ground and the hole is in-filled with soil 26 (or other appropriate fill material, including for example crushed gravel, concrete, etc.), the sleeve conforms fairly closely to the post because the soil 26 compresses the sleeve 12 against the post 16.

There are numerous plastic compounds that are appropriate for sleeve 12, including as noted polyethylene; other polymers will work suitably well, too. The polyethylene may include compounds that enhance the stability of the sleeve over long periods of time and exposure to moisture in the ground and to conditions existing in subsurface conditions. The material used for sleeve 12 should be thick enough to be puncture and tear resistant in use; a standard thickness of about 6 mil has been found to be effective although the thickness may vary as appropriate. Importantly, the sleeve must be wholly intact at all points where the sleeve encases the post in the ground in order to define a waterproof barrier around the post. The length of the sleeve extending between the bottom portion 22 and the open top 24 is sufficient that the sleeve extends a slight distance above ground level 18 when the post 16 is in the ground.

Collar 14 defines a length of collar material that surrounds post 16 immediately above ground level 18 and which is attached to the post and encircles the open top of sleeve 12 to prevent moisture and debris from entering the open top of the sleeve. As detailed below, the collar 14 is designed to allow evaporation of moisture from the interior of the sleeve 12, prevent UV radiation from impinging on the sleeve 12, and prevent water and other debris from entering the sleeve. As shown in FIGS. 2 through 5, collar 14 is defined by a length of material that is wrapped around the post 16—the lineal length of collar 14 is roughly equal to the circumference around post 16 where the collar surrounds the post.

Beginning with the lowermost edge 30 of collar 14, which generally rests on or adjacent to the surface of ground 18 in the assembled apparatus (FIG. 1), a vertical sidewall portion 32 extends upwardly to an inwardly and upwardly sloping edge section 34. The sloping edge section 34 defines a stand-off so that the vertical sidewall portion 32 is spaced apart from the post 16, as detailed below. Immediately adjacent sloping edge section 34 is a vertical sidewall section 36 that defines a seat for the connecting band that attaches the collar 14 to the post. Vertical sidewall section 36 includes a thickened edge portion 38 at the junction between the vertical section 36 and the sloping edge section 34, and an outwardly projecting lip 40 at the upper extent of the vertical section 36. The combined thickened section 38 and upper outwardly projecting lip 40 at opposite sides of the vertical section 36 effectively define a circumferential groove 42 around which the connecting band extends. Above vertical section 36 and outwardly projecting lip 40 is a second inwardly and upwardly sloping section, referred to herein as sealing section 44. As detailed below, sealing section 44 defines a seal between collar 14 and the post 16 in the assembled product.

For reference purposes, the exterior surface of collar 14 is identified in the drawings with reference number 46—the exterior surface 46 is exposed to the elements when the collar is in place around a post 16. The opposite surface of collar 14, that is, the surface that faces post 16 is identified as interior surface 48. An upwardly and inwardly sloping lip 50 is formed on interior surface 48 of collar 14 below and adjacent to the junction between the vertical sidewall section 32 and the sloping edge section 34. Plural vent openings 52 are formed in collar 14 above lip 50 and below the junction between the vertical sidewall section 32 and the sloping edge section 34.

Collar 14 is formed from a flexible, malleable material that is waterproof and resistant to degradation from ultraviolet radiation. A thermoplastic elastomer sold under the brand name SANTOPRENE is one material that has found to exhibit good properties for use in collar 14. While a variety of colors may be used for collar 14, the preferred color is black. The collar is provided in an extruded roll and the collar is cut to an appropriate length by the installer; the lineal length of the collar 14 as used with a post 16 is the same as or slightly greater than the circumference of the post where the collar surrounds the post just above the level of ground 18, as shown in FIG. 1.

With specific reference to FIG. 4, preferred but exemplary specifications for collar 14 are detailed, although it will be understood that the size, shape and form of the collar may be varied as required in any given installation. The overall height of collar 14 is represented as dimension A, and is preferably approximately 3½ inches. Seal 44 is angled at about a 69 degree angle from the vertical sidewall 32, and lip 50 is angled at about a 45 degree angle from the vertical sidewall 32. The thickness of the collar between the junction between the vertical sidewall section 32 and the sloping edge section 34 and extending upwardly to the outwardly projecting lip is slightly greater than the thickness of the collar below the junction between the vertical sidewall section 32 and the sloping edge section 34. This added thickness results in a slightly more rigid upper portion of the collar.

Returning to FIG. 1, apparatus 10 is illustrated installed on a post 16. Initially, a hole 54 is dug in the ground with the appropriate diameter for the post 16 that will be inserted into the hole, and at the proper depth. The post 16 is then inserted into the open top 24 of an appropriately sized sleeve 12 and the sleeve is pulled onto the post until the bottom of the sleeve rests against the bottom of the post. The sleeve-covered post is then inserted into the hole 54. The edge of the sleeve 12 at the open top 24 should extend above the level of ground 18 by several inches. If the sleeve is too long it may be trimmed to the proper length. A properly sized sleeve 12 is slightly larger in diameter than past 12 so the sleeve does not fit tightly to the irregular contours of the post. Fill material such as soil 26 is then filled into the post hole 54 and the post 16 is adjusted to the desired orientation relative to the ground, typically vertically oriented.

The circumference of post 12 immediately above the level of ground 18 is then measured and a length of collar 14 is cut to the length of the circumference, or slightly greater. This is best shown in FIG. 2 where the length of collar 12 has opposite ends 56 and 58. The collar 12 is then wrapped around the post 16 and the portion of sleeve 12 that extends above ground level, as seen in FIG. 1, with the base 30 of the collar resting on or adjacent to the surface of ground 18. The collar is then pulled snug around the pole 16 and the ends 56 and 58 are mated to one another (and if the length of the piece of collar is longer than the circumference of the post, the ends 56 and 58 are overlapped over one another) and the collar may then optionally be held temporarily in place with a staple or tack (not shown). A fastener 60 is then wrapped around the collar at circumferential groove 42 between edge 38 and lip 40 and is tightened in place. There are numerous types of fasteners that will work for fastener 60. In FIG. 1, fastener 60 is a standard hose clamp of the type having a screw-driven worm gear. Other suitable fasteners include conventional nylon cable ties and zip ties, lap joint clamps, etc. The fastener 60 is tightened around the collar 14 and the post 16 to hold the collar securely in place on the post.

As an alternative method of attaching collar 14 to post 16, the opposite ends 56 and 58 of the collar may be tacked or stapled to the underlying post and the fastener 60 may be omitted.

As best illustrated in FIG. 5, when the collar 14 is secured in place on post 16 with a fastener 60, the inwardly projecting seal 44 at the upper edge of the collar is deflected upwardly so that the interior surface 62 of the seal 44 rests flush against the surface of the post 16. In addition, the interior surface of the collar opposite fastener 60 lies flush against the surface of the post with the fastener compressing the collar material against the post. All wooden posts will have irregularities in their outer surfaces. However, because the collar 14 is malleable and flexible, the combination of the collar-to-post contact at seal 44 and the collar-to-post contact beneath the fastener 60, the collar effectively seals around the post at the upper end of the collar.

Immediately below edge 38, the collar 14 diverges outwardly away from post 16 at sloping edge section 34. Again as best seen in FIG. 1, the collar 14 is thus spaced apart from post 16 below edge 38 to define a space 62 that extends completely to the level of ground 18. The portion of sleeve 12 that extends above ground 18 is captured loosely within space 62. Inward lip 50 lies above the upper edge of open top 24 of sleeve 12, but the lip 50 does not touch the outer surface of post 16 and is spaced apart from it. Sleeve 12 is not tightly conformed to post 16 where the sleeve is in space 62. As such, there is a space 66 between the sleeve and the post and a passageway is defined from space 66 over the open top 24 of sleeve 12, past lip 50 and through the plural holes 52. Passageway 66 includes the open top 24 of sleeve 12 and is schematically illustrated in FIG. 5 with arrow A.

Most wooden posts have some residual moisture that wicks away from the post and evaporates over time. The passageway 66 thus allows water vapor that evaporates from the post, even in the portions of the post below the level of ground 18 to escape from the collar. External water such as rain and irrigation water cannot enter space 62 through holes 52 because lip 50 is sloped upwardly (relative to the ground plane) and blocks water from entering the space. Moreover, the lip 50 effectively blocks UV radiation from hitting sleeve 12. This prevents degradation of the sleeve over extended periods of time.

The combination of sleeve 12 and collar 14 defines an effective apparatus and method for enhancing the life of in-ground wood. It will be appreciated by those of skill in the art that a variety of structural changes may be made to the sleeve and collar relative to the embodiments disclosed above without departing from the nature and scope of the invention.

While the present invention has been described in terms of preferred and illustrated embodiments, it will be appreciated by those of ordinary skill that the spirit and scope of the invention is not limited to those embodiments, but extend to the various modifications and equivalents as defined in the appended claims. 

1. Apparatus for use with wooden in-ground posts having a portion extending below ground level and a portion extending above ground level, comprising: a waterproof sleeve surrounding the below ground portion of said post and a portion of said sleeve extending above the ground level; a waterproof collar adapted for being wrapped around said post and having a lower edge on or adjacent to the ground level, an upper edge sealed against said post, and a lower section that is spaced apart from said post around said post, wherein said portion of said sleeve that extends above the ground level is contained in the lower portion of said collar that is spaced apart from said post.
 2. The apparatus according to claim 1 including plural holes in said collar opening into said lower portion of said collar that is spaced apart from said post.
 3. The apparatus according to claim 2 wherein said collar includes an interior wall that is spaced apart from said post, and including a lip formed on the interior wall below said plural holes.
 4. The apparatus according to claim 3 wherein said lip has a distal end and the distal end is spaced apart from said post.
 5. The apparatus according to claim 4 wherein said portion of said sleeve that extends above the ground level is contained in the lower portion of said collar that is spaced apart from said post, below said lip.
 6. The apparatus according to claim 5 including a fluid flow path from the spaced apart portion past said lip and through said plural holes.
 7. The apparatus according to claim 3 wherein said lip is positioned relative to said plural holes to block sunlight entering through said holes from impinging on said sleeve.
 8. The apparatus according to claim 7 wherein said lip is position relative to said plural holes to prevent watering from entering the lower portion of said collar that is spaced apart from said post.
 9. The apparatus according to claim 1 wherein said collar includes a circumferential seat between the upper edge and the lower portion and including a fastener extending around said collar in said circumferential seat.
 10. The apparatus according to claim 1 wherein the collar defines a wall thickness and the wall thickness at the lower section is relatively less than the wall thickness at the upper edge.
 11. Apparatus for use with wooden in-ground posts having a portion extending below ground level and a portion extending above ground level, comprising: a waterproof sleeve adapted for surrounding the below ground portion of said post wherein a portion of said sleeve extends above the ground level to define a space between the post and said sleeve, said sleeve having an open top, a closed bottom and closed sidewalls, and a circumference greater than the circumference of the in-ground post; a waterproof collar adapted to be wrapped around said post at the ground level and having a lower edge on or adjacent to the ground level, an upper edge sealed against said post, and a lower section that is spaced apart from said post around said post around the circumference thereof, wherein said portion of said sleeve that extends above the ground level is contained in the lower portion of said collar that is spaced apart from said post, and said waterproof collar defining a fluid flow path from the space between the post and the sleeve; and said waterproof collar including water and light blocking means for preventing water and light from outside of said collar from entering the space between the post and the sleeve.
 12. The apparatus according to claim 11 wherein the fluid flow path from the space between the post and the sleeve is defined by plural holes in said collar opening into said lower portion of said collar that is spaced apart from said post.
 13. The apparatus according to claim 12 wherein said light blocking means for preventing water and light from outside of said collar from entering the space between the post and the sleeve is defined by an interior wall that is spaced apart from said post with a lip formed on the interior wall below said plural holes and extending circumferentially around said collar.
 14. The apparatus according to claim 13 wherein said lip has a distal end and the distal end is spaced apart from said post.
 15. The apparatus according to claim 14 wherein said lip is positioned relative to said plural holes to block sunlight entering through said holes from impinging on said sleeve.
 16. A method for use with a wooden in-ground post having a portion extending below ground level and a portion extending above ground level, for extending the effective life of said post, comprising the steps of: a) forming a hole in the ground for receiving said post; b) providing a post; c) covering a lower portion of said post with a waterproof sleeve and inserting said post in said hole so that a portion of said waterproof sleeve extends above the ground level; d) in-filling the hole; e) wrapping a waterproof collar having opposite ends around said post so that a bottom edge of the collar is on or adjacent to ground level, mating the opposite ends of said collar and securing the collar to the post so that an upper portion of said collar is sealed against said post and a lower portion of said collar is spaced apart from said post, and wherein a portion of said waterproof sleeve that extends above the ground level is captured between the collar and the post in the spaced apart portion.
 17. The method according to claim 16 including the step of providing holes in said collar in said spaced apart portion to define a fluid flow path from said post into said spaced apart portion and through said holes.
 18. The method according to claim 16 of allowing moisture from said post to evaporate therefrom through the fluid flow path.
 19. The method according to claim 18 including the step of blocking light and water from entering said spaced apart portion.
 20. The method according to claim 16 wherein the step of securing the collar to the post includes the step of wrapping a tie around the upper portion of the collar and tightening the tie against the collar. 